红萍在植物治污方面的应用研究进展

植物治污是利用植物清除土壤和水中的各类污染物 ,进行环境治理。水生蕨类植物红萍具有一定的耐污能力 ,可以通过植物活体的富集作用和干体的物理吸附作用 ,从溶液中吸附多种重金属元素及通过植物挥发作用 ,将吸入的硒盐转化为挥发态。在污水中养萍可以去除COD和进行生物脱氮除磷 ,并设计出相应的养萍盘和生物稳定塘系统进行废水处理 ;利用红萍干体填充的滤柱可以用于电镀污水中一些重金属元素吸附回收。本文对红萍近年来在植物治污方面的应用和研究进行了描述和展望     

粤北岩溶区的石漠化及其治理对策探讨

粤北岩溶石山地区分布有面积广泛的碳酸盐岩发育多种岩溶地貌。由于该地区的特殊地质、水文、气候等自然因子的影响，其岩溶生态环境脆弱，环境容量低，敏感度高，抗干扰能力弱。在不合理的人类活动和自然因素作用下，易引发出一系列的生态问题。岩溶生态环境开始恶化，植被走向逆向演替等，最后出现大面积的石山，发生石演化观象。     

离子色谱法测定标样中硫酸根含量的测量不确定度评定

通过对离子色谱法测定标样中硫酸根含量的过程研究,分析了该方法测定结果的不确定度来源,并对各不确定度分量进行了评定.     

Comparison of PM2.5 carbon measurement methods in Hong Kong, China

Samples from Hong Kong, China, were analyzed for organic carbon (OC), elemental carbon (EC), and total carbon (TC) by three thermal protocols (low-temperature IMPROVE and high-temperature STN and NIOSH) and two optical monitoring methods: reflectance and transmittance. Good agreement (+/-10%) for TC among the three protocols was observed for sample loadings of 1-55 microg m(-3). The two protocols using a reflectance pyrolysis correction showed best agreement for EC, with <20% differences found for approximately 80% of the samples. Hong Kong has a large diesel fleet, and for some heavily loaded samples the light transmittance was too low for quantitative detection, resulting in large uncertainties in the OC/EC split based on transmittance. Hong Kong experienced OC levels similar to those at US sites, but has much higher EC concentrations. OC/EC ratios range from 2 to 5 at two US sites and from 0.2 to 1.2 at three Hong Kong sites.     

污染土壤修复效果评定方法的研究

在实施污染土壤修复的环境工程后,需要通过灵敏和有效的评定方法对污染土壤修复的效果进行评定.然而,单纯依靠化学方法进行污染土壤修复效果的评定,不能揭示土壤的整体质量特征,因此需要生态毒理方法作为相互补充的手段.本文概述了植物毒性评定法、陆生无脊椎动物评定法和土壤微生物评定法及其在污染土壤修复效果评定中的应用,并对污染土壤修复效果评定方法的发展前景进行展望.     

无机陶瓷纳滤膜分离高钠盐废水中的锶

本实验研究表明,仅用截留分子量为1000的无机陶瓷纳滤膜分离高钠盐模拟溶液中的锶,分离效果并不理想.为提高陶瓷纳滤膜对锶的选择分离效果,选择了分子量为3000的聚丙烯酸作为陶瓷纳滤膜分离的强化剂,重点探讨了溶液pH值、聚丙烯酸浓度、温度及离子强度对模拟溶液盐分离效果和膜通量的影响,并得到了适宜的锶钠分离条件.实验结果表明,在适宜条件下,通过聚丙烯酸强化和两级分离,陶瓷纳滤膜可大大提高模拟溶液中锶离子的选择分离效果,锶/钠的分离因子高达205.     

射流曝气的气液两相流的数值模拟

射流曝气在活性污泥处理方法中起着重要的作用。采用数值模拟的方法研究自吸式单级单喷射流器中的气液两相流动状况，通过对不同长径比和喷嘴面积比的射流曝气器模型的气液两相流的计算，定量分析长径比和喷嘴面积比对射流曝气器流场和空气与工作介质流量比的影响，为进一步设计开发新型高效的射流曝气器提供参考。     

生物质废弃物催化裂解制备富氢燃气实验研究

由生物质废弃物催化裂解制取氢气是一种可再生的制氢方法，本研究采用2段加热管式反应器，前段装生物质，后段装催化剂，用以研究生物质催化裂解制取氢气的特性，并提出潜在氢产率的概念对生物质制氢的经济技术可行性进行深入的分析。测试的3种生物质废弃物为：松木粉、木质素和纤维素，测试温度为600～700℃。实验结果表明，加入催化剂后3种物料的产氢率从5．48～15．06g／kg增加到12．94～37．73g／kg；催化剂对潜在产氢率的影响较小，加入催化剂前后的变化范围为：36、25～98、86g／kg到37．40～116．98g／kg。生物质废弃物催化裂解产氢率与相同温度下空气-水蒸气气化的氢产率相当，实验结果证明，生物质废弃物催化裂解是一种有效的制氢方法。     

Generation pattern of sulfur containing gases from anaerobically digested sludge cakes.

Eleven dewatered sludge cakes collected from anaerobic digesters at different treatment plants were evaluated for the amount, type, and pattern of odorous gas production. All but one of the sludge cakes were from mesophilic anaerobic digesters. One was from a thermophilic digester. The pattern and quantities of sulfur gases were found to be unique for each of the samples with regard to the products produced, magnitude, and subsequent decline. The main odor-causing chemicals were volatile sulfur compounds, which included hydrogen sulfide, methanethiol, and dimethyl sulfide. Volatile sulfur compound production peaked in 3 to 8 days and then declined. The decline was a result of conversion of organic sulfur compounds to sulfide. In one side-by-side test, a high-solids centrifuge cake generated more odorous compounds than the low-solids centrifuge cake. The data show that anaerobic digestion does not eliminate the odor potential of anaerobically digested dewatered cakes.     

Removal of carbon dioxide by a spray dryer

With the global warming due to greenhouse effects becoming serious, many efforts are carried out to decrease the emissions of CO2 from the combustion of carbonaceous materials. In Taiwan, there are 19 large-scale municipal solid waste incinerators running and their total emission of CO2 is about 16,950 kton y-1. Spray dryer is the most prevailing air pollution control devise for removing acid gas in waste incineration; however, the performance of spray dryer on the removal of CO2 is seldom studied. This study employs a laboratory-scale spray dryer to investigate the removal efficiency of CO2 under different operating conditions. The evaluated parameters include different absorbents mixed with CaOH2, operating temperature, the concentration of absorbent, and the inlet concentration of CO2. Experimental results show that the best removal efficiency of CO2 by a spray dryer is 48% as the absorbent is 10%NaOH+5%CaOH2 and the operating temperature is 150 degrees C. Comparing this result with previous study shows that the performance of spray dryer is better than traditional NaOH wet scrubber. For NaOH+CaOH2 spray dryer, the removal efficiency of CO2 is decreased with the inlet concentration of CO2 increased and the optimum operating temperature is 150 degrees C. Except NaOH+CaOH2, absorbents DEA+CaOH2, TEA+CaOH2, and single CaOH2 are not effective in removing CO2 by a spray dryer.